At an open-house meeting on Wednesday night, the parks department asked for public input on a parking-meter option for Echo Canyon Park, the parking lot for Piestewa Peak area, and Pima Canyon in the South Mountain Preserve. Several dozen people showed up to complain about the plan.

People who didn't go to the meeting can still give their two-cents' worth by calling 602-261-8318 or emailing pks.phoenix.mountain.preserves.parking@phoenix.gov.

The question of whether to charge for parking at the city's most popular trailheads has long been a sticky one, with many people criticizing the possibility. Yet parking problems are only growing worse, begging for some kind of solution.

A $4.3 million renovation at Camelback's Echo Canyon trailhead last year roughly doubled the number of parking spaces, from 66 to 135. But since the January 16 reopening of Echo Canyon, the trail's popularity seems to have only increased. The Echo Canyon lot is often filled to the max whenever the temperature is under triple digits. Meanwhile, backups at Piestewa Peak are common, and at Pima Canyon in the cooler months, hikers and mountain bikers need to arrive early to get a parking spot.

Options like providing a monthly pass or taking money at the gate could cause even more backups, says Ken Vonderscher, deputy director of Phoenix Parks and Recreation.

The city could simply install the meters and be done with it. But receiving the public's input before taking that step is "important," he says. "We need to walk it through."

Officials take "visitor experience" into account, and they realize "it probably wouldn't be popular with a lot of people to have fees," Vonderscher says.

Even if the parking plan went into effect, it would cover only three of 40 parking lots in Phoenix mountain-preserve areas, he says. While about 500 spaces would be "fee-based," another 5,300 spaces would still be free. The city hopes to encourage people to use its other trail systems, both to help with parking and reduce erosion on the most popular trails.

Vonderscher acknowledges it may be tough to convince people to use other trails, since the amenities at Pima Canyon, Camelback and Piestewa provide the steepest vertical gains in the city's preserves, and also happen to be located conveniently in the middle of the Valley.

The city's meters cost $1.50 an hour for now, but will be increasing as of October to a range of between 50 cents to $4 an hour, depending on where they're located. The potential cost of trailhead meters hasn't been yet determined. While some people can hike Echo Canyon trail or the Piestewa Peak summit trail in 90 minutes or faster, others take hours to cover the same ground. Mountain bikers and hikers at South Mountain sometimes ride for hours at a time -- maybe even all day. The meters will have to take that into account.

Whether meters are the answer or not, the intense popularity of the three areas under review means that limitations on trail users are probably inevitable.